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    <td bgcolor="#666699" width="10"><b><a href="http://irrlicht.sourceforge.net" target="_blank"><img src="../../media/irrlichtlogo.jpg" width="88" height="31" border="0"></a></b></td>
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        <div align="left"><b><font color="#FFFFFF">Tutorial 12. Terrain Rendering</font></b></div>
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        <p> This tutorial will briefly show how to use the terrain renderer of 
          Irrlicht. It will also show the terrain renderer triangle selector to 
          be able to do collision detection with terrain.</p>
        <p>The program which is described here will look like this:</p>
        <p align="center"><img src="../../media/012shot.jpg" width="258" height="202"></p>
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          Note that the terrain renderer in Irrlicht is based the terrain renderer 
          by Soconne and the GeoMipMapSceneNode developed by Spinz, lots of thanks 
          go to them.</p>
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    <td bgcolor="#666699"> <b><font color="#FFFFFF">Lets start!</font></b></td>
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          <p> In the beginning there is nothing special. We include the needed 
            header files and create an event listener to listen if the user presses 
            the 'W' key so we can switch to wireframe mode and if he presses 'D' 
            we toggle to material between solid and detail mapped.</p>
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              <td> <pre>#include &lt;irrlicht.h&gt;<br>#include &lt;iostream&gt;<br>using namespace irr;<br><br>#pragma comment(lib, &quot;Irrlicht.lib&quot;)<br><br>class MyEventReceiver : public IEventReceiver<br>{<br>public:<br>	MyEventReceiver(scene::ISceneNode* terrain)<br>	{<br><font color="#006600">		// store pointer to terrain so we can change its drawing mode<br></font>		Terrain = terrain;<br>	}<br><br>	bool OnEvent(const SEvent& event)<br>	{<br>	<font color="#006600">	// check if user presses the key 'W' or 'D'</font><br>		if (event.EventType == irr::EET_KEY_INPUT_EVENT &amp;&amp; !event.KeyInput.PressedDown)<br>		{<br>			switch (event.KeyInput.Key)<br>			{<br>			case irr::KEY_KEY_W:<font color="#006600"> // switch wire frame mode</font><br>				Terrain-&gt;setMaterialFlag(video::EMF_WIREFRAME, !Terrain-&gt;getMaterial(0).Wireframe);<br>				return true;<br>			case irr::KEY_KEY_D:<font color="#006600"> // toggle detail map</font><br>				Terrain-&gt;setMaterialType(<br>					Terrain-&gt;getMaterial(0).MaterialType == video::EMT_SOLID ? <br>					video::EMT_DETAIL_MAP : video::EMT_SOLID);<br>				return true;<br>			}<br>		}<br>		return false;<br>	}<br><br>private:<br>	scene::ISceneNode* Terrain;<br>};<br><br></pre></td>
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          <p>The start of the main function starts like in most other example. 
            We ask the user for the desired renderer and start it up. </p>
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              <td> <pre>int main()<br>{<br><font color="#006600">	// let user select driver type<br></font><br>	video::E_DRIVER_TYPE driverType = video::EDT_DIRECT3D9;<br><br>	printf(&quot;Please select the driver you want for this example:\n&quot;\<br>		&quot; (a) Direct3D 9.0c\n (b) Direct3D 8.1\n (c) OpenGL 1.5\n&quot;\<br>		&quot; (d) Software Renderer\n (e) Apfelbaum Software Renderer\n&quot;\<br>		&quot; (f) NullDevice\n (otherKey) exit\n\n&quot;);<br><br>	char i;<br>	std::cin &gt;&gt; i;<br><br>	switch(i)<br>	{<br>		case 'a': driverType = video::EDT_DIRECT3D9;break;<br>		case 'b': driverType = video::EDT_DIRECT3D8;break;<br>		case 'c': driverType = video::EDT_OPENGL;   break;<br>		case 'd': driverType = video::EDT_SOFTWARE; break;<br>		case 'e': driverType = video::EDT_BURNINGSVIDEO;break;<br>		case 'f': driverType = video::EDT_NULL;     break;<br>		default: return 1;<br>	}	<br><font color="#006600"><br>	// create device<br></font>	IrrlichtDevice* device = createDevice(driverType, core::dimension2d&lt;s32&gt;(640, 480));<br><br>	if (device == 0)<br>		return 1; <font color="#006600">// could not create selected driver.</font><br></pre></td>
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          <p> First, we add standard stuff to the scene: A nice irrlicht engine 
            logo, a small help text, a user controlled camera, and we disable 
            the mouse cursor.</p>
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              <td> <pre>video::IVideoDriver* driver = device-&gt;getVideoDriver();<br>scene::ISceneManager* smgr = device-&gt;getSceneManager();<br>gui::IGUIEnvironment* env = device-&gt;getGUIEnvironment();<br><br>driver-&gt;setTextureCreationFlag(video::ETCF_ALWAYS_32_BIT, true);<br><br><font color="#006600">// add irrlicht logo<br></font>env-&gt;addImage(driver-&gt;getTexture(&quot;../../media/irrlichtlogoalpha.tga&quot;),<br>    core::position2d&lt;s32&gt;(10,10));<br>
<font color="#006600">// add some help text<br></font>gui::IGUIStaticText* text = env-&gt;addStaticText(<br>	L&quot;Press 'W' to change wireframe mode\nPress 'D' to toggle detail map&quot;,<br>	core::rect&lt;s32&gt;(10,453,200,475), true, true, 0, -1, true);<br>
<font color="#006600">// add camera<br></font>scene::ICameraSceneNode* camera = <br>    smgr-&gt;addCameraSceneNodeFPS(0,100.0f,1200.0f);<br>camera-&gt;setPosition(core::vector3df(1900*2,255*2,3700*2));<br>camera-&gt;setTarget(core::vector3df(2397*2,343*2,2700*2));<br>camera-&gt;setFarValue(12000.0f);<br><br><font color="#006600">// disable mouse cursor<br></font>device-&gt;getCursorControl()-&gt;setVisible(false);</pre></td>
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          <p> Here comes the terrain renderer scene node: We add it just like 
            any other scene node to the scene using ISceneManager::addTerrainSceneNode(). 
            The only parameter we use is a file name to the heightmap we use. 
            A heightmap is simply a gray scale texture. The terrain renderer loads 
            it and creates the 3D terrain from it.<br>
            To make the terrain look more big, we change the scale factor of it 
            to (40, 4.4, 40). Because we don't have any dynamic lights in the 
            scene, we switch off the lighting, and we set the file terrain-texture.jpg 
            as texture for the terrain and detailmap3.jpg as second texture, called 
            detail map. At last, we set the scale values for the texture: The 
            first texture will be repeated only one time over the whole terrain, 
            and the second one (detail map) 20 times. </p>
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              <td> <pre><font color="#006600">// add terrain scene node<br></font>scene::ITerrainSceneNode* terrain = smgr-&gt;addTerrainSceneNode( <br>      &quot;../../media/terrain-heightmap.bmp&quot;);<br><br>terrain-&gt;setScale(core::vector3df(40, 4.4f, 40));<br>terrain-&gt;setMaterialFlag(video::EMF_LIGHTING, false);<br><br>terrain-&gt;setMaterialTexture(0, driver-&gt;getTexture(&quot;../../media/terrain-texture.jpg&quot;));<br>terrain-&gt;setMaterialTexture(1, driver-&gt;getTexture(&quot;../../media/detailmap3.jpg&quot;));<br>	<br>terrain-&gt;setMaterialType(video::EMT_DETAIL_MAP);<br>terrain-&gt;scaleTexture(1.0f, 20.0f);<font color="#006600"><br></font></pre></td>
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          <p> To be able to do collision with the terrain, we create a triangle 
            selector. If you want to know what triangle selectors do, just take 
            a look into the collision tutorial. The terrain triangle selector 
            works together with the terrain. To demonstrate this, we create a 
            collision response animator and attach it to the camera, so that the 
            camera will not be able to fly through the terrain. </p>
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            <td> <pre><font color="#006600">// create triangle selector for the terrain	<br></font>scene::ITriangleSelector* selector =<br>    smgr-&gt;createTerrainTriangleSelector(terrain, 0);<br>terrain-&gt;setTriangleSelector(selector);<br><br><font color="#006600">// create collision response animator and attach it to the camera<br></font>scene::ISceneNodeAnimator* anim = smgr-&gt;createCollisionResponseAnimator(<br>	selector, camera, core::vector3df(60,100,60),<br>	core::vector3df(0,0,0), <br>	core::vector3df(0,50,0));<br>selector-&gt;drop();<br>camera-&gt;addAnimator(anim);<br>anim-&gt;drop();</pre></td>
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        <p> To make the user be able to switch between normal and wireframe mode, 
          we create an instance of the event reciever from above and let Irrlicht 
          know about it. In addition, we add the skybox which we already used 
          in lots of Irrlicht examples.</p>
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            <td><pre><font color="#006600">// create event receiver<br></font>MyEventReceiver receiver(terrain);<br>device-&gt;setEventReceiver(&amp;receiver);<br><br><font color="#006600">// create skybox<br></font>driver-&gt;setTextureCreationFlag(video::ETCF_CREATE_MIP_MAPS, false);<br><br>smgr-&gt;addSkyBoxSceneNode(<br>	driver-&gt;getTexture(&quot;../../media/irrlicht2_up.jpg&quot;),<br>	driver-&gt;getTexture(&quot;../../media/irrlicht2_dn.jpg&quot;),<br>	driver-&gt;getTexture(&quot;../../media/irrlicht2_lf.jpg&quot;),<br>	driver-&gt;getTexture(&quot;../../media/irrlicht2_rt.jpg&quot;),<br>	driver-&gt;getTexture(&quot;../../media/irrlicht2_ft.jpg&quot;),<br>	driver-&gt;getTexture(&quot;../../media/irrlicht2_bk.jpg&quot;));<br>
driver-&gt;setTextureCreationFlag(video::ETCF_CREATE_MIP_MAPS, true);<br></pre></td>
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        <p> That's it, draw everything. Now you know how to use terrain in Irrlicht.</p>
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            <td><pre>	int lastFPS = -1;<br><br>	while(device-&gt;run())<br>	if (device-&gt;isWindowActive())<br>	{<br>		driver-&gt;beginScene(true, true, 0 );<br><br>		smgr-&gt;drawAll();<br>		env-&gt;drawAll();<br><br>		driver-&gt;endScene();
<br><font color="#006600">		// display frames per second in window title
</font>		int fps = driver-&gt;getFPS();<br><br>		if (lastFPS != fps)<br>		{<br>			core::stringw str = L&quot;Terrain Renderer - Irrlicht Engine [&quot;;<br>			str += driver-&gt;getName();<br>			str += &quot;] FPS:&quot;;<br>			str += fps;<br>			device-&gt;setWindowCaption(str.c_str());<br>			lastFPS = fps;<br>		}<br>	}<br><br>	device-&gt;drop();<br>	<br>	return 0;<br>}</pre></td>
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        <p>&nbsp; </p>
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<p>&nbsp;</p>
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